test(agentx): trigger fast-mode sweep

Author: cquil11

perf-changelog.yaml

@@ -5236,4 +5236,5 @@
   description:
     - "Pin shared AIPerf to c57ad643 and replace duration-based warmup with 10 deterministic requests per lane."
     - "Use one warmup request per lane with the 20-minute agentx-fast profile, and emit TTFT, ITL, and throughput metrics every 30 seconds."
+    - "Trigger an agentx-fast validation sweep on the existing Kimi K3 B300 AgentX configuration."
   pr-link: https://github.com/SemiAnalysisAI/InferenceX/pull/2415